1. Technical Field
The present disclosure generally relates to a method and apparatus for searching and pairing peripheral Bluetooth devices.
2. Description of the Related Art
Bluetooth technology provides wireless communication without using cables and wires in a short range. Bluetooth technology uses a 2.4 GHz Industrial Scientific Medical (ISM) radio band that does not require a license for use.
Bluetooth technology is used to connect a printer, a keyboard, or a mouse to a Personal Computer (PC) including a laptop computer and a desktop computer. Bluetooth technology is also used in data transmission between various mobile terminals such as a Personal Digital Assistant (PDA), a mobile phone, a smart phone, a tablet computer, and a laptop computer. Further, it allows a headset, an earphone, or a speaker to wirelessly connect to a mobile terminal.
For communication between Bluetooth devices, pairing needs to be performed. In order for one Bluetooth device to be paired with another Bluetooth device, the Bluetooth device performs an inquiry process for searching nearby peripheral Bluetooth devices. The Bluetooth device which searches for the peripheral Bluetooth devices is a master device.
The master device transmits an inquiry message for searching nearby peripheral Bluetooth devices. A slave device close to the master device, upon receiving an inquiry message, sends an inquiry response message to the master device. The inquiry response message includes a Bluetooth device address of the slave device. The master device, upon receiving the inquiry response message, sends a remote name request message for requesting a remote name of the slave device. The remote name is a name of the Bluetooth device, for example, a model name of the Bluetooth device. The slave device, upon receiving the remote name request message, sends a remote name response message including its remote name to the master device.
The master device, upon finding one peripheral Bluetooth device or plural peripheral Bluetooth devices according to the inquiry process, displays a Bluetooth device list showing names of the found one or plural peripheral Bluetooth devices through a display. Thus, a user may recognize Bluetooth devices which may be paired from the Bluetooth device list. If the user selects a desired Bluetooth device with which the user desires pairing from the Bluetooth device list, then the master device sends a pairing request to the Bluetooth device selected by the user. Thus, pairing between the master device and the desired Bluetooth device by the user may be performed.
However, during the inquiry process, a Frequency Hopping Synchronization (FHS) scheme is used between the master device and the slave device, and the slave device scans channels based on FHS at a predetermined scan interval. Thus, even when the Bluetooth device with which the user desires the pairing among the peripheral Bluetooth devices is located closest to the master device, the closest Bluetooth device may not be first detected. Moreover, when a number of Bluetooth devices are merely included in the Bluetooth device list, the user may not easily distinguish the desired Bluetooth device the pairing from the other Bluetooth devices.
As an attempt to solve these problems, the Bluetooth device list may be displayed after being sorted based on a Received Signal Strength Indication (RSSI) of each of the Bluetooth devices of the Bluetooth device list, or an automatic pairing may be performed with a Bluetooth device having the highest RSSI. For later, the user moves the Bluetooth device, which is desired to be paired with the master device, close to the master device, such that the RSSI of the desired Bluetooth device may be measured higher in the master device than other peripheral Bluetooth devices. However, in operation, due to different power classes for different types of Bluetooth devices, the RSSIs are not correctly matched with the Bluetooth device list. For example, a Bluetooth device such as a Personal Computer (PC) is typically on the top of the Bluetooth device list. As a result, the reliability of sorting or automatic pairing based on the RSSIs of the found Bluetooth devices is not high, and a Bluetooth device other than the desired Bluetooth device may be automatically paired with the master device.